Characterization of two monoclonal antibodies which recognize different subpopulations of chicken T lymphocytes.

Distribution among peripheral T lymphocyte subpopulations and biochemical properties of the chicken lymphocyte surface antigens defined by monoclonal antibodies (mAbs) Lc-4 and Lc-6 were examined. Two-color immunofluorescence analysis revealed that Lc-4 and Lc-6 antigens were expressed on mutually exclusive subpopulations of peripheral T lymphocytes but not on B lymphocytes. Lc-4 mAb precipitated a polypeptide with apparent molecular mass of 35 and 65 kilodalton under reducing and non-reducing conditions, respectively. These results indicated that the antigen recognized with Lc-4 was closely similar in tissue distribution and biochemical property to mammalian CD8 antigen.